CVE-2026-101917

PyJWT: PyJWKClient still amplifies unauthenticated JWKS fetches on unknown kid values (incomplete fix of CVE-2026-48524)

HIGH
7.5
CVSS Score
Published: September 28, 2026 at 08:07 PM UTC
Updated: October 7, 2026 at 09:01 PM UTC
2 products affected across 2 vendorsPyjwtPyjwt

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Severity
HIGH7.5
Exploit prediction
EPSS 0.4%
SSVC
PoC

Description

PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, PyJWT get_signing_key_from_jwt is affected because unknown kid misses force refreshes without a negative cache or minimum refresh interval. This occurs when unauthenticated tokens repeatedly use the same unknown kid or varying kid values absent from the cached JWKS. As a result, each cache miss causes PyJWKClient to refresh the JWKS. Consequently, attacker traffic can amplify outbound requests to the configured JWKS endpoint. This issue is fixed in version 2.14.0.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 2.14.0
Affected range stops below 2.14.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (3)

x_refsource_CONFIRMExploitVendor Advisory
Source: cverecord
https://github.com/jpadilla/pyjwt/security/advisories/GHSA-2gx3-rcp4-g85q
x_refsource_MISCProductRelease Notes
Source: cverecord
https://github.com/jpadilla/pyjwt/releases/tag/2.14.0

SSVC — Action Prioritization

SSVCPoCAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-770

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